DOCSLIB.ORG

Effects of Ageratina Adenophora Invasion on the Understory

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Effects of Ageratina Adenophora Invasion on the Understory Article Effects of Ageratina adenophora Invasion on the Understory Community and Soil Phosphorus Characteristics of Different Forest Types in Southwest China Xiaoni Wu 1,2,3, Changqun Duan 1,3 , Denggao Fu 1,3,*, Peiyuan Peng 1,3, Luoqi Zhao 1,3 and Davey L. Jones 4,5 1 School of Ecology and Environmental Science & Yunnan Key Laboratory for Plateau Mountain Ecology and Restoration of Degraded Environments, Yunnan University, Kunming 650091, China; [email protected] (X.W.); [email protected] (C.D.); [email protected] (P.P.); [email protected] (L.Z.) 2 School of Agriculture and Life Sciences, Kunming University, Kunming 650214, China 3 International Cooperative Center of Plateau Lake Ecological Restoration and Watershed Management of Yunnan, Yunnan University, Kunming 650091, China 4 School of Natural Sciences, Bangor University, Gwynedd LL57 2UW, UK; [email protected] 5 UWA School of Agriculture and Environment, University of Western Australia, Perth, WA 6009, Australia * Correspondence: [email protected]; Tel./Fax: +86-871-6503-3629 Received: 17 June 2020; Accepted: 23 July 2020; Published: 25 July 2020 Abstract: Understanding the influence of invasive species on community composition and ecosystem properties is necessary to maintain ecosystem functions. However, little is known about how understory plant communities and soil nutrients respond to invasion under different land cover types. Here, we investigated the effects of the invasive species Ageratina adenophora on the species and functional diversity of understory communities and on soil phosphorus (P) status in three forest types: CF, coniferous forest; MF, coniferous and broadleaf mixed forest; and EBF, evergreen broadleaf forest. We found that the species and functional diversity indices of the understory community significantly varied by forest type. Among the invaded plots, the greatest decrease in functional diversity (functional richness, functional divergence, and functional dispersion) and biotic homogenization were found in the CF rather than the MF or EBF. In addition, the invasion by A. adenophora significantly increased the soil NaHCO3-extractable inorganic P and organic P in the MF and EBF, respectively, while obviously decreasing the soil maximum P sorption capacity and maximum buffering capacity in the CF. However, the changes in the species and functional attributes of the understory communities were weakly associated with changes in the soil P status, probably because of the different response times to invasion in different forest types. The implication of these changes for ecosystem structure and function must be separately considered when predicting and managing invasion at a landscape scale. Keywords: biological invasion; functional diversity; understory community; soil phosphorus fractions; soil phosphorus sorption characteristics 1. Introduction Alien plant species invasion is recognized as a serious threat to biodiversity and ecosystem functions [1–3]. Invasive plants can affect natural and semi-natural habitats by displacing native species and changing the nutrient status of the soil [4,5]. Some studies have reported that non-native species invasion may affect terrestrial ecosystem processes and functions via changes in plant community Forests 2020, 11, 806; doi:10.3390/f11080806 www.mdpi.com/journal/forests Forests 2020, 11, 806 2 of 14 composition or soil properties [6,7]. However, many of the observed impact patterns may depend on many confounding factors of the landscape, including the influence of different land cover types [8]. Thus, understanding the influence of invasive species on biodiversity and ecosystem functions in different land cover types can improve spread predictions and reduce ecosystem impacts due to invasive plant species. The effect of invasion is frequently associated with biodiversity loss; however, changes in the plant species composition and diversity may take many years to play out, especially in forest ecosystems. However, increasingly, research is devoted to plant functional traits, exploring how changes in the functional attributes of plant communities affect ecosystem functions and their response to environmental changes [9,10]. Furthermore, trait-based approaches are being used to examine how invasion affects ecosystem structure and functions [11,12]. In forest ecosystems, invasive species may have a detrimental effect on the understory vegetation, which in turn plays a critical role in ecosystem functions [13,14]. Hence, analysing the response of plant functional attributes within the understory community to invasion and the relationships between functional attributes and ecosystem functions might help detect early vegetation responses and ecosystem function alterations. However, the responses of plant functional attributes to invasion and their feedback to ecosystem processes and functions is likely to vary among different forest types. Among ecosystem processes and functions, the effect of invasion on the soil phosphorus (P) cycle is less understood than the effect of invasion on the carbon (C) and nitrogen (N) cycles [15–17]. Most studies on the modification of the P cycle due to exotic species typically focus on the total P (TP) and inorganic P (Pi) forms [18], and less data exist on the impacts of exotic plants on P fractions and P dynamics. Among soil P fractions, Pi extracted with deionized water (water-Pi) and NaHCO3 (bicarb-Pi) are considered the most biologically and readily available Pi forms, and Po extracted with NaHCO3 (bicarb-Po) is easily mineralizable and may contribute to plant-available Pi [18]. In invaded ecosystems, exotic species can affect the distribution and fluxes of easily available P in soil at short- and medium-term time scales, by changing the soil microbial community or soil physicochemical properties [19–21]. However, different patterns of changes in the soil P fraction have been observed in some studies, because the direction and degree of changes in P cycling may depend on many confounding factors, including the specifics of site conditions, land use type, and the biological characteristics of exotic species [22–24]. Therefore, the measurement of easily available P and P behaviour characteristics, together with vegetation properties, is required to better understand the relationships among invasion, vegetation composition, and soil P cycling. The invasive herb Ageratina adenophora, a perennial shrub native to Mexico, invaded China in the 1940s from Burma and is now widespread in Southwest China [22]. In this region, invasion by A. adenophora has a profound influence on the composition, structure, and function of the impacted forest ecosystems because of its clonal reproduction and competitive advantage [16,25]. However, there are few quantitative data on the effects of A. adenophora on understory community composition and soil P status in different forest types. In this study, three typical forest types in Xishan National Forest Park bordering Dianchi Lake, a substantially eutrophic water body in Southwest China, were selected to investigate the invasion effect on understory communities and soil P status, P fraction and P sorption characteristics. Our aims were (1) to determine the effects of invasion by A. adenophora on the understory plant community and soil P status (including the easily available P fractions and P sorption characteristics) in the three forest types, and (2) to quantify the effects of invasion on the relationships between understory plant community properties and soil P status. 2. Materials and Methods 2.1. Site Description The study was carried out at Xishan National Forest Park (102◦37~380 E, 24◦57~590 N), nearby Kunming city, Yunnan Province, China. This park borders Dianchi Lake to the east. Owing to the Forests 2020, 11, 806 3 of 14 influenceForests 2019 of,the 10, x southwestern FOR PEER REVIEW monsoon climate, the average annual precipitation in the area is 11003 of mm.14 The rainy season lasts from May to October each year. The mean annual temperature is 14.7 ◦C. Themm. soils The in rainy the study season area lasts are from classified May to October as Cambisols each year. (according The mean to annual FAO/UNESCO temperature classifications), is 14.7 °C. whichThe developedsoils in the fromstudy basaltarea are parent classified material. as Ca Thembisols original (according vegetation to FAO/UNESCO was a semi-humid classifications), evergreen broadleavedwhich developed forest, from some basalt of which parent was material. utilized The as coppicesoriginal vegetation for fuelwood was a after semi-humid deforestation evergreen before thebroadleaved 1960s. Since forest, the 1980s,some of some which of was these utilized have beenas coppices planted for by fuelwoodPinus armandii after deforestationand P. yunnanensis before afterthedeforestation. 1960s. Since the Due1980s, to some the long-termof these have preservation been planted of by some Pinus originalarmandii vegetationand P. yunnanensis and di afterfferent restorationdeforestation. measures, Due to thethe diversitylong-term ofpreservation vegetation of shows some original a patchy vegetation distribution. and different The main restoration vegetation measures, the diversity of vegetation shows a patchy distribution. The main vegetation types are types are semi-humid evergreen broadleaf forest, coniferous and broadleaf mixed forest, and subtropical semi-humid evergreen broadleaf forest, coniferous and broadleaf mixed forest, and subtropical coniferous forest. In this area, these three forest types with similar conditions,
Load more

Recommended publications
  • Biological Control of Two Ageratina Species (Asteraceae: Eupatorieae) in South Africa
    Biological control of two Ageratina species (Asteraceae: Eupatorieae) in South Africa F. Heystek1*, A.R. Wood2, S. Neser1 & Y. Kistensamy1 1Agricultural Research Council-Plant Protection Research Institute, Private Bag X134, Queenswood, 0121 South Africa 2Agricultural Research Council-Plant Protection Research Institute, Private Bag X5017, Stellenbosch, 7599 South Africa Ageratina adenophora (Spreng.) R.M.King & H.Rob. and Ageratina riparia (Regel) R.M.King & H.Rob. (Asteraceae: Eupatorieae), originally from Mexico, are invasive in many countries. These plants produce thousands of wind- and water-dispersed seeds which enable them to spread rapidly and invade stream banks and moist habitats in areas with high rainfall. Two biological control agents, a shoot-galling fly, Procecidochares utilis Stone (Diptera: Tephri- tidae), and a leaf-spot fungus, Passalora ageratinae Crous & A.R. Wood (Mycosphaerellales: Mycosphaerellaceae), were introduced against A. adenophora in South Africa in 1984 and 1987, respectively. Both established but their impact is considered insufficient. Exploratory trips to Mexico between 2007 and 2009 to search for additional agents on A. adenophora produced a gregarious leaf-feeding moth, Lophoceramica sp. (Lepidoptera: Noctuidae), a stem-boring moth, probably Eugnosta medioxima (Razowski) (Lepidoptera: Tortricidae), a leaf-mining beetle, Pentispa fairmairei (Chapuis) (Coleoptera: Chrysomelidae: Cassidinae), and a leaf-rust, Baeodromus eupatorii (Arthur) Arthur (Pucciniales: Pucciniosiraceae) all of which have been subjected to preliminary investigations. Following its success in Hawaii, the white smut fungus, Entyloma ageratinae R.W. Barreto & H.C. Evans (Entylomatales: Entylomataceae), was introduced in 1989 to South Africa against A. riparia. Its impact has not been evaluated since its establishment in 1990 in South Africa. By 2009, however, A.
    [Show full text]
  • Ageratina Riparia Global Invasive Species Database (GISD)
    FULL ACCOUNT FOR: Ageratina riparia Ageratina riparia System: Terrestrial Kingdom Phylum Class Order Family Plantae Magnoliophyta Magnoliopsida Asterales Asteraceae Common name Synonym Eupatorium riparium , Regel Similar species Summary Ageratina riparia is a popular ornamental plant that has been widely spread from its home region in Central America. It is naturalised in many tropical regions of the world and is invasive in some such as Hawaii, Australia and the islands of the Indian Ocean. It can form dense quasi monospecific stands which crowd out native plants, limiting their regeneration. view this species on IUCN Red List Principal source: Compiler: Comité français de l'UICN (IUCN French Committee) & IUCN SSC Invasive Species Specialist Group (ISSG) Review: Pubblication date: 2008-03-14 ALIEN RANGE [1] AUSTRALIA [2] MAURITIUS [1] NEW ZEALAND [1] REUNION [1] UNITED STATES Red List assessed species 3: EX = 2; EN = 1; Mixophyes fleayi EN Rheobatrachus silus EX Taudactylus diurnus EX BIBLIOGRAPHY 7 references found for Ageratina riparia Managment information General information Global Invasive Species Database (GISD) 2021. Species profile Ageratina riparia. Pag. 1 Available from: http://www.iucngisd.org/gisd/species.php?sc=1253 [Accessed 06 October 2021] FULL ACCOUNT FOR: Ageratina riparia Baret, S., Rouget, M., Richardson, D. M., Lavergne, C., Egoh, B., Dupont, J., & Strasberg, D. 2006. Current distribution and potential extent of the most invasive alien plant species on La R?union (Indian Ocean, Mascarene islands). Austral Ecology, 31, 747-758. Summary: L objectif de ce papier est d identifier les zones prioritaires en mati?re de gestion des invasions biologiques ? La R?union en mod?lisant la distribution actuelle et potentiellle d une s?lection de plantes parmi les plus envahissantes.
    [Show full text]
  • Ha'iwale Cyrtandra Polyantha
    No Photo Available Plants Ha‘iwale Cyrtandra polyantha SPECIES STATUS: Federally Listed as Endangered Genetic Safety Net Species IUCN Red List Ranking ‐ CR B1ab(iii); C2a(i) Hawai‘i Natural Heritage Ranking ‐ Critically Imperiled (G1) Endemism – O‘ahu Critical Habitat ‐ Designated SPECIES INFORMATION: Cyrtandra polyantha, a member of the African violet family, is an unbranched or few‐branched shrub 3 to 10 ft (1 to 3 m) in height. Its leathery, elliptic, unequal leaves are 2 to 6.3 in (5 to 16 cm) long and 0.7 to 2 in (1.8 to 5.2 cm) wide and attached oppositely along the stems. The upper surface of the leaf is conspicuously wrinkled and usually hairless, with the lower surface moderately to densely covered with pale brown hairs. Seven to 12 flowers are grouped in branched clusters in the leaf axils. The white petals, fused to form a cylindrical tube about 0.5 in (12 mm) long, emerge from a radically symmetrical calyx, 0.2 in (5 mm) long, that is cleft from one‐half to two‐thirds its length. Each calyx lobe, narrowly triangular in shape, is sparsely hairy on the outside and hairless within. The fruits are white oval berries about 0.6 in (1.8 cm) long that contain many seeds about 0.02 in (0.5 mm) long. Cyrtandra polyantha is distinguished from other species in the genus by the texture and hairiness of the leaf surfaces and the length, shape, and degree of cleft of the calyx. This species differs from C. crenota by the lack of short‐stalked glands and by its leathery leaves, opposite leaf arrangement, and radially symmetrical calyx.
    [Show full text]
  • HAWAII and SOUTH PACIFIC ISLANDS REGION - 2016 NWPL FINAL RATINGS U.S
    HAWAII and SOUTH PACIFIC ISLANDS REGION - 2016 NWPL FINAL RATINGS U.S. ARMY CORPS OF ENGINEERS, COLD REGIONS RESEARCH AND ENGINEERING LABORATORY (CRREL) - 2013 Ratings Lichvar, R.W. 2016. The National Wetland Plant List: 2016 wetland ratings. User Notes: 1) Plant species not listed are considered UPL for wetland delineation purposes. 2) A few UPL species are listed because they are rated FACU or wetter in at least one Corps region. Scientific Name Common Name Hawaii Status South Pacific Agrostis canina FACU Velvet Bent Islands Status Agrostis capillaris UPL Colonial Bent Abelmoschus moschatus FAC Musk Okra Agrostis exarata FACW Spiked Bent Abildgaardia ovata FACW Flat-Spike Sedge Agrostis hyemalis FAC Winter Bent Abrus precatorius FAC UPL Rosary-Pea Agrostis sandwicensis FACU Hawaii Bent Abutilon auritum FACU Asian Agrostis stolonifera FACU Spreading Bent Indian-Mallow Ailanthus altissima FACU Tree-of-Heaven Abutilon indicum FAC FACU Monkeybush Aira caryophyllea FACU Common Acacia confusa FACU Small Philippine Silver-Hair Grass Wattle Albizia lebbeck FACU Woman's-Tongue Acaena exigua OBL Liliwai Aleurites moluccanus FACU Indian-Walnut Acalypha amentacea FACU Alocasia cucullata FACU Chinese Taro Match-Me-If-You-Can Alocasia macrorrhizos FAC Giant Taro Acalypha poiretii UPL Poiret's Alpinia purpurata FACU Red-Ginger Copperleaf Alpinia zerumbet FACU Shellplant Acanthocereus tetragonus UPL Triangle Cactus Alternanthera ficoidea FACU Sanguinaria Achillea millefolium UPL Common Yarrow Alternanthera sessilis FAC FACW Sessile Joyweed Achyranthes
    [Show full text]
  • The Chaparral Vegetation in Mexico Under Nonmediterranean Climate: the Convergence and Madrean-Tethyan Hypotheses Reconsidered1
    American Journal of Botany 85(10): 1398±1408. 1998. THE CHAPARRAL VEGETATION IN MEXICO UNDER NONMEDITERRANEAN CLIMATE: THE CONVERGENCE AND MADREAN-TETHYAN HYPOTHESES RECONSIDERED1 ALFONSO VALIENTE-BANUET,2,4 NOEÂ FLORES-HERNAÂ NDEZ,2 MIGUEL VERDUÂ ,3 AND PATRICIA DAÂ VILA3 2Instituto de EcologõÂa, Universidad Nacional AutoÂnoma de MeÂxico, Apartado Postal 70±275, UNAM, 04510 MeÂxico, D.F.; and 3UBIPRO, ENEP-Iztacala, Universidad Nacional AutoÂnoma de MeÂxico, Apartado Postal 314, MeÂxico, 54090, Tlalnepantla, MeÂxico A comparative study between an unburned evergreen sclerophyllous vegetation located in south-central Mexico under a wet-summer climate, with mediterranean regions was conducted in order to re-analyze vegetation and plant characters claimed to converge under mediterranean climates. The comparison considered ¯oristic composition, plant-community struc- ture, and plant characters as adaptations to mediterranean climates and analyzed them by means of a correspondence analysis, considering a tropical spiny shrubland as the external group. We made a species register of the number of species that resprouted after a ®re occurred in 1995 and a distribution map of the evergreen sclerophyllous vegetation in Mexico (mexical) under nonmediterranean climates. The TehuacaÂn mexical does not differ from the evergreen sclerophyllous areas of Chile, California, Australia, and the Mediterranean Basin, according to a correspondence analysis, which ordinated the TehuacaÂn mexical closer to the mediter- ranean areas than to the external group. All the vegetation and ¯oristic characteristics of the mexical, as well as its distribution along the rain-shadowed mountain parts of Mexico, support its origin in the Madrean-Tethyan hypothesis of Axelrod. Therefore, these results allow to expand the convergence paradigm of the chaparral under an integrative view, in which a general trend to aridity might explain ¯oristic and adaptive patterns detected in these environments.
    [Show full text]
  • BIOLOGICAL OPINION of the U.S. FISH and WILDLIFE SERVICE for ROUTINE MILITARY TRAINING and TRANSFORMATION of the 2Nd BRIGADE 25Th INFANTRY DIVISION (Light)
    BIOLOGICAL OPINION of the U.S. FISH AND WILDLIFE SERVICE for ROUTINE MILITARY TRAINING and TRANSFORMATION of the 2nd BRIGADE 25th INFANTRY DIVISION (Light) U.S. ARMY INSTALLATIONS ISLAND of OAHU October 23, 2003 (1-2-2003-F-04) TABLE OF CONTENTS INTRODUCTION ........................................................... 1 CONSULTATION HISTORY .................................................. 2 BIOLOGICAL OPINION Description of the Proposed Action ............................................ 6 Dillingham Military Reservation ............................................... 11 Kahuku Training Area ..................................................... 15 Kawailoa Training Area .................................................... 20 Makua Military Reservation ................................................. 24 Schofield Barracks East Range ............................................... 25 Schofield Barracks Military Reservation ........................................ 29 South Range Acquisition Area ............................................... 35 Other Proposed SBCT Training Action Locations ................................. 36 Wildland Fire Management Plan Overview ...................................... 37 Stabilization Overview ..................................................... 38 Conservation Measures .................................................... 42 STATUS OF THE SPECIES AND ENVIRONMENTAL BASELINE - PLANTS Abutilon sandwicense ..................................................... 52 Alectryon macrococcus ..................................................
    [Show full text]
  • Evaluating the Development and Potential Ecological Impact of Genetically Engineered Taraxacum Kok-Saghyz
    Evaluating the Development and Potential Ecological Impact of Genetically Engineered Taraxacum kok-saghyz DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University By Brian J. Iaffaldano Graduate Program in Horticulture and Crop Science The Ohio State University 2016 Dissertation Committee: Professor Katrina Cornish, Advisor Professor John Cardina Professor David Francis Professor Allison Snow Copyrighted by Brian J. Iaffaldano 2016 Abstract Natural rubber is a biopolymer with irreplaceable properties, necessary in tires, medical devices and many other applications. Nearly all natural rubber production is dependent on a single species, Hevea brasiliensis. Hevea has several disadvantages, including a long life cycle, epidemic diseases, and rising production costs which have led to interest in developing new sources of rubber with similar quality to Hevea. One species that meets this criterion is Taraxacum kok-saghyz (TK), a widely adapted species of dandelion that can produce substantial amounts of rubber in its roots in an annual growing period. Shortcomings of TK include an inability to compete with many weeds, resulting in poor establishment and yields. In addition, there is variability in the amount of rubber produced, plant vigor, and seed establishment. In order to address these shortcomings, genetic engineering or breeding may be used to introduce herbicide resistance and allocate more resources to rubber production. We have demonstrated stable transformation in Taraxacum species using Agrobacterium rhizogenes to introduce genes of interest as well has hairy root phenotypes. Inoculated roots were subjected to selection by kanamycin and glufosinate and allowed to regenerate into plantlets without any hormonal treatments or additional manipulations.
    [Show full text]
  • Effects of Slope Aspect on Ageratina Adenophora (Spreng.) King & H
    2021 Journal of Plant Resources Vol.19, No. 1 Effects of Slope Aspect on Ageratina adenophora (Spreng.) King & H. Rob. Density and Galls Formed by Its Natural Enemy Procecidochares utilis Stone, 1947 in Makwanpur, Nepal Seeta Pathak1, Tej Bahadur Darji1, Reetu Deuba1, Gunanand Pant2, Ramesh Raj Pant3 & Lal B Thapa1* 1Central Department of Botany, Tribhuvan University, Kathmandu, Nepal 2Department of Biology, Kailali Multiple Campus, Kailali, Nepal 3Central Department of Environmental Science, Tribhuvan University, Kathmandu, Nepal * Email: [email protected] Abstract A forest killer plant, Ageratina adenophora (Spreng.) King & H. Rob., has become a highly problematic weed in Nepal. Its control and management is a challenging issue. Studies on different factors that impact on its invasiveness are still deficient. On the other hand, assessment of its biological control agent, the Procecidochares utilis Stone, 1947 in Nepal remains untouched. This study aims to analyze the impacts of slope aspect on A. adenophora density and the galls formed by P. utilis in Central Nepal. The study revealed that the slope aspect influences theA. adenophora plant density, number of gall-bearing plants and gall density. These parameters were the highest in the south-east facing slope comparing to the north-west facing slope indicating that the infestation by P. utilis depends on the aspects. The findings of this study will have significance in developing management strategies for A. adenophora with the application of P. utilis as a biological control agent in Nepal. Keyword: Biocontrol agent, Biological control, Forest killer plant, Gall fly, Invasive alien species, Kalo banmara Introduction Several eco-geographical factors such as elevation, native species diversity and distribution, canopies Ageratina adenophora (Spreng.) King & H.
    [Show full text]
  • Ageratina Adenophora (Spreng.) R
    CA LIF ORNIA D EPA RTM EN T OF FOOD & AGRICULTURE California Pest Rating Proposal for Ageratina adenophora (Spreng.) R. M. King and H. Rob.: croftonweed, thoroughwort, sticky snakeroot, Family Asteraceae tribe Eupatorieae Current Pest Rating: Z Proposed Pest Rating: B Synonym: Eupatorium adenophorum Spreng., E. glandulosum Michx. Comment Period: 04/16/2021 through 05/31/2021 Initiating Event: This species has been rated Z by CDFA and is a Federal noxious weed species, but has not previously undergone the pest rating proposal process. History & Status: Background: Croftonweed, Ageratina adenophora, is a perennial herb with woody base or a subshrub that can grow up to 2 meters in height (Keil, 2012; Nesom, 2006). The stems are erect, purplish in color when young, and glandular-hairy. The leaves are opposite, ovate-lanceolate to nearly triangular with serrate margin, glandular-hairy and purplish below. The petiole is approximately 1-2.5 cm long and the leaf blade approximately 2-10 cm long. The small discoid heads are approximately 6-7 mm long and borne in flat cymose clusters. The involucre of the head and subtending peduncle are densely glandular-hairy. The disc corollas are white or pink-tinged. The one-seeded brownish to black cypsela fruits are approximately 1.5-2 mm in length, glabrous, with five angles and ribs, and bear an easily detached pappus of slender, whitish, minutely barbed bristles approximately 2-4 mm in length. In California the species occurs in disturbed areas, coastal canyons, riparian areas, scrub, and montane hillsides with adequate permanent water or fog drip (CalIPC, 2021: CCH, 2021).
    [Show full text]
  • Asteraceae: Eupatorieae) from 0Axaco, Mexico and a Key to the A
    NUMBER 9 TURNER: THREE NEW SPECIES OF AGERATINA THREE NEW SPECIES OF AGERATINA (ASTERACEAE: EUPATORIEAE) FROM 0AXACO, MEXICO AND A KEY TO THE A. MAIRETIANA COMPLEX Billie L. Turner Plant Resources Center, The University of Texas, Austin, Texas 78712, USA Abstract: Three new species of Ageratina subg. Neogreenella are described from Mex­ ico, as follows: Ageratina mayajana, from Mpio. San Miguel Chimalapa, Oaxaca; Ageratina mazatecana, from Mpio. Santa Maria Chilchotla, Oaxaca; and Ageratina pochutlana from Districto Pochutla, Oaxaca. Although all of the taxa belong to the A. subg. Neogreenella, only the latter two relate to the A. mairetiana complex as defined by Turner (1987, 1997). A revised key to that complex is provided. Keywords: Asteraceae, Eupatorieae, Ageratina, Mexico, Oaxaca. As treated by Turner (1997), the Mex­ from or near the base, 9-15 cm long, 2.5- ican species of Ageratina number 131. The 3.5 cm wide, sparsely pubescent above and following three novelties bring the total to below to nearly glabrous, the margins re­ 134. motely serrate. HEADS numerous, arranged in terminal rounded cymes 5-15 cm across, Ageratina mayajana B. L. Turner, sp. nov. the ultimate peduncles sparsely hispidulous, (Fig. 1) mostly 2-10 mm long. INVOLUCRES broad­ ly campanulate; bracts subimbricate, 2-3 TYPE: MEXICO. OAXACA. Mpio. San seriate, the inner series ca. 3 mm long. RE­ Miguel, Chimalapa, Cerro Verde, al S del CEPTACLE convex, ca. 1 mm across, gla­ camino Benito Juarez-La Cienega, ca. 8 km brous. FLORETS 40-50 per head; corollas ca. en linea recta al SE de Benito Juarez, ca.
    [Show full text]
  • Seed Longevity and Dormancy State in a Disturbance-Dependent Forest Herb, Ageratina Altissima
    Seed Science Research (2016) 26, 148–152 doi:10.1017/S0960258516000052 © Cambridge University Press 2016 Seed longevity and dormancy state in a disturbance-dependent forest herb, Ageratina altissima Mame E. Redwood1, Glenn R. Matlack1* and Cynthia D. Huebner2 1Environmental and Plant Biology, Porter Hall, Ohio University, Athens, Ohio 45701, USA; 2Northern Research Station, USDA Forest Service, Morgantown, West Virginia, USA (Received 2 October 2015; accepted after revision 9 February 2016; first published online 10 March 2016) Abstract organisms to persist in heterogeneous, dynamic land- scapes (Venable and Brown, 1988). The guild of gap- Does seed dormancy allow disturbance-oriented forest dependent forest herbs allows a test of this hypothesis. herbs such as Ageratina altissima to persist in heteroge- Whereas most temperate-zone forest herb species show neous natural communities? To document seed longev- little seed dormancy and only occasionally appear in ity and dormancy state, Ageratina seeds were buried the soil seed bank (Matlack and Good, 1990; Hyatt in nylon mesh bags in second-growth forest stands in and Casper, 2000; Leckie et al., 2000), a subset of forest south-eastern Ohio, USA. Bags were recovered at herbs does appear in seed banks. These species are 2-month intervals, and seeds were tested for viability generally recognizable by their low tolerance of and germinability in the lab. Live seed numbers shade, small seeds, effective dispersal and opportunis- declined rapidly, with seed banks exhausted in an esti- tic use of forest gaps (Jankowska-Blaszczuk and – mated 33 37 months. Seeds showed a strong dor- Grubb, 1997; Hyatt and Casper, 2000). Canopy gaps – mancy polymorphism, with 71 84% of live seeds are isolated and ephemeral microhabitats, placing germinable between March and July, the season of severe limitations on the life histories of light- natural seedling emergence.
    [Show full text]
  • ORIGINAL RESEARCH Plant Invasion Research in Nepal: a Review Of
    ORIGINAL RESEARCH Plant Invasion Research in Nepal: A Review of Recent National Trends Mohan Pandey1, Khum Bahadur Thapa-Magar2, Buddhi Sagar Poudel3, Thomas Seth Davis2, Bharat Babu Shrestha4, * 1 KTK-BELT, Inc., Kathmandu, Nepal, 2 Department of Forest and Rangeland Stewardship, Warner College of Natural Resources, Colorado State University, Fort Collins, USA. 3 REDD Implementation Centre, Ministry of Forests and Environment, Kathmandu, Nepal 4 Central Department of Botany, Tribhuvan University, Kathmandu, Nepal Corresponding Author E-mail: [email protected] Received: 31 May 2020 Accepted for publication: 28 September 2020 Published: 30 December 2020 ______________________________________________________________________________________ Abstract Research interests in Invasive Alien Plant Species (IAPS) have expanded globally, and nationally in Nepal, over the last few decades. Here we provide a systematic compilation and analysis of the scientific literature to explore research trends and identify research gaps in plant invasion biology in Nepal. We compiled and examined journal publications retrieved from Web of Science (WOS) and other databases (NepJOL, Google Scholar, and other bibliographies) using specific search keywords. The search yielded 86 research studies on IAPS, published between 1958 and 2020 (up to August 2020) that met our pre-determined criteria. The number of publications in national journals that focused on IAPS increased, starting in 2000, but this increase was not notable in international journals, until 2010. Nearly 91 % of the studies that appeared in international journals were published after 2010. A majority of the studies focus on biology, ecology, and ecological impact studies of a few selected IAPS, especially mile-a-minute (Mikania micrantha Kunth), parthenium weed (Parthenium hysterophorus L.), and crofton weed (Ageratina adenophora (Spreng.) R.M.
    [Show full text]